test/java/lang/Double/ParseDouble.java
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rev 7487 : 7192954: Fix Float.parseFloat to round correctly and preserve monotonicity.
4396272: Parsing doubles fails to follow IEEE for largest decimal that should yield 0
7039391: Use Math.ulp in FloatingDecimal
Summary: Correct rounding and monotonicity problems in floats and doubles
Reviewed-by: martin
Contributed-by: Dmitry Nadezhin <dmitry.nadezhin@oracle.com>, Louis Wasserman <lowasser@google.com>
@@ -21,24 +21,110 @@
* questions.
*/
/*
* @test
- * @bug 4160406 4705734 4707389 4826774 4895911 4421494 7021568 7039369
+ * @bug 4160406 4705734 4707389 4826774 4895911 4421494 6358355 7021568 7039369 4396272
* @summary Test for Double.parseDouble method and acceptance regex
*/
-import java.util.regex.*;
import java.math.BigDecimal;
+import java.math.BigInteger;
+import java.util.regex.*;
public class ParseDouble {
+ private static final BigDecimal HALF = BigDecimal.valueOf(0.5);
+
+ private static void fail(String val, double n) {
+ throw new RuntimeException("Double.parseDouble failed. String:" +
+ val + " Result:" + n);
+ }
+
+ private static void check(String val) {
+ double n = Double.parseDouble(val);
+ boolean isNegativeN = n < 0 || n == 0 && 1/n < 0;
+ double na = Math.abs(n);
+ String s = val.trim().toLowerCase();
+ switch (s.charAt(s.length() - 1)) {
+ case 'd':
+ case 'f':
+ s = s.substring(0, s.length() - 1);
+ break;
+ }
+ boolean isNegative = false;
+ if (s.charAt(0) == '+') {
+ s = s.substring(1);
+ } else if (s.charAt(0) == '-') {
+ s = s.substring(1);
+ isNegative = true;
+ }
+ if (s.equals("nan")) {
+ if (!Double.isNaN(n)) {
+ fail(val, n);
+ }
+ return;
+ }
+ if (Double.isNaN(n)) {
+ fail(val, n);
+ }
+ if (isNegativeN != isNegative)
+ fail(val, n);
+ if (s.equals("infinity")) {
+ if (na != Double.POSITIVE_INFINITY) {
+ fail(val, n);
+ }
+ return;
+ }
+ BigDecimal bd;
+ if (s.startsWith("0x")) {
+ s = s.substring(2);
+ int indP = s.indexOf('p');
+ long exp = Long.parseLong(s.substring(indP + 1));
+ int indD = s.indexOf('.');
+ String significand;
+ if (indD >= 0) {
+ significand = s.substring(0, indD) + s.substring(indD + 1, indP);
+ exp -= 4*(indP - indD - 1);
+ } else {
+ significand = s.substring(0, indP);
+ }
+ bd = new BigDecimal(new BigInteger(significand, 16));
+ if (exp >= 0) {
+ bd = bd.multiply(BigDecimal.valueOf(2).pow((int)exp));
+ } else {
+ bd = bd.divide(BigDecimal.valueOf(2).pow((int)-exp));
+ }
+ } else {
+ bd = new BigDecimal(s);
+ }
+ BigDecimal l, u;
+ if (Double.isInfinite(na)) {
+ l = new BigDecimal(Double.MAX_VALUE).add(new BigDecimal(Math.ulp(Double.MAX_VALUE)).multiply(HALF));
+ u = null;
+ } else {
+ l = new BigDecimal(na).subtract(new BigDecimal(Math.ulp(Math.nextUp(-na))).multiply(HALF));
+ u = new BigDecimal(na).add(new BigDecimal(Math.ulp(n)).multiply(HALF));
+ }
+ int cmpL = bd.compareTo(l);
+ int cmpU = u != null ? bd.compareTo(u) : -1;
+ if ((Double.doubleToLongBits(n) & 1) != 0) {
+ if (cmpL <= 0 || cmpU >= 0) {
+ fail(val, n);
+ }
+ } else {
+ if (cmpL < 0 || cmpU > 0) {
+ fail(val, n);
+ }
+ }
+ }
+
private static void check(String val, double expected) {
double n = Double.parseDouble(val);
if (n != expected)
- throw new RuntimeException("Double.parseDouble failed. String:" +
- val + " Result:" + n);
+ fail(val, n);
+ check(val);
}
private static void rudimentaryTest() {
check(new String(""+Double.MIN_VALUE), Double.MIN_VALUE);
check(new String(""+Double.MAX_VALUE), Double.MAX_VALUE);
@@ -458,10 +544,11 @@
for(int i = 0; i < input.length; i++) {
double d;
try {
d = Double.parseDouble(input[i]);
+ check(input[i]);
}
catch (NumberFormatException e) {
if (! exceptionalInput) {
throw new RuntimeException("Double.parseDouble rejected " +
"good string `" + input[i] +
@@ -558,16 +645,17 @@
/**
* For each subnormal power of two, test at boundaries of
* region that should convert to that value.
*/
private static void testSubnormalPowers() {
+ boolean failed = false;
BigDecimal TWO = BigDecimal.valueOf(2);
// An ulp is the same for all subnormal values
BigDecimal ulp_BD = new BigDecimal(Double.MIN_VALUE);
- // Test subnormal powers of two
- for(int i = -1074; i <= -1022; i++) {
+ // Test subnormal powers of two (except Double.MIN_VALUE)
+ for(int i = -1073; i <= -1022; i++) {
double d = Math.scalb(1.0, i);
/*
* The region [d - ulp/2, d + ulp/2] should round to d.
*/
@@ -576,21 +664,73 @@
BigDecimal lowerBound = d_BD.subtract(ulp_BD.divide(TWO));
BigDecimal upperBound = d_BD.add(ulp_BD.divide(TWO));
double convertedLowerBound = Double.parseDouble(lowerBound.toString());
double convertedUpperBound = Double.parseDouble(upperBound.toString());
+ if (convertedLowerBound != d) {
+ failed = true;
+ System.out.printf("2^%d lowerBound converts as %a %s%n",
+ i, convertedLowerBound, lowerBound);
+ }
+ if (convertedUpperBound != d) {
+ failed = true;
+ System.out.printf("2^%d upperBound converts as %a %s%n",
+ i, convertedUpperBound, upperBound);
}
}
+ /*
+ * Double.MIN_VALUE
+ * The region ]0.5*Double.MIN_VALUE, 1.5*Double.MIN_VALUE[ should round to Double.MIN_VALUE .
+ */
+ BigDecimal minValue = new BigDecimal(Double.MIN_VALUE);
+ if (Double.parseDouble(minValue.multiply(new BigDecimal(0.5)).toString()) != 0.0) {
+ failed = true;
+ System.out.printf("0.5*MIN_VALUE doesn't convert 0%n");
+ }
+ if (Double.parseDouble(minValue.multiply(new BigDecimal(0.50000000001)).toString()) != Double.MIN_VALUE) {
+ failed = true;
+ System.out.printf("0.50000000001*MIN_VALUE doesn't convert to MIN_VALUE%n");
+ }
+ if (Double.parseDouble(minValue.multiply(new BigDecimal(1.49999999999)).toString()) != Double.MIN_VALUE) {
+ failed = true;
+ System.out.printf("1.49999999999*MIN_VALUE doesn't convert to MIN_VALUE%n");
+ }
+ if (Double.parseDouble(minValue.multiply(new BigDecimal(1.5)).toString()) != 2*Double.MIN_VALUE) {
+ failed = true;
+ System.out.printf("1.5*MIN_VALUE doesn't convert to 2*MIN_VALUE%n");
+ }
+ if (failed)
+ throw new RuntimeException("Inconsistent conversion");
+ }
+
+ /**
+ * For each power of two, test at boundaries of
+ * region that should convert to that value.
+ */
+ private static void testPowers() {
+ for(int i = -1074; i <= +1023; i++) {
+ double d = Math.scalb(1.0, i);
+ BigDecimal d_BD = new BigDecimal(d);
+
+ BigDecimal lowerBound = d_BD.subtract(new BigDecimal(Math.ulp(Math.nextUp(-d))).multiply(HALF));
+ BigDecimal upperBound = d_BD.add(new BigDecimal(Math.ulp(d)).multiply(HALF));
+
+ check(lowerBound.toString());
+ check(upperBound.toString());
+ }
+ check(new BigDecimal(Double.MAX_VALUE).add(new BigDecimal(Math.ulp(Double.MAX_VALUE)).multiply(HALF)).toString());
+ }
private static void testStrictness() {
- final double expected = 0x0.0000008000001p-1022;
+ final double expected = 0x0.0000008000000p-1022;
+// final double expected = 0x0.0000008000001p-1022;
boolean failed = false;
double conversion = 0.0;
double sum = 0.0; // Prevent conversion from being optimized away
- //2^-1047 + 2^-1075
+ //2^-1047 + 2^-1075 rounds to 2^-1047
String decimal = "6.631236871469758276785396630275967243399099947355303144249971758736286630139265439618068200788048744105960420552601852889715006376325666595539603330361800519107591783233358492337208057849499360899425128640718856616503093444922854759159988160304439909868291973931426625698663157749836252274523485312442358651207051292453083278116143932569727918709786004497872322193856150225415211997283078496319412124640111777216148110752815101775295719811974338451936095907419622417538473679495148632480391435931767981122396703443803335529756003353209830071832230689201383015598792184172909927924176339315507402234836120730914783168400715462440053817592702766213559042115986763819482654128770595766806872783349146967171293949598850675682115696218943412532098591327667236328125E-316";
for(int i = 0; i <= 12_000; i++) {
conversion = Double.parseDouble(decimal);
sum += conversion;
@@ -618,8 +758,9 @@
testRegex(paddedGoodStrings, false);
testRegex(badStrings, true);
testRegex(paddedBadStrings, true);
testSubnormalPowers();
+ testPowers();
testStrictness();
}
}